Correct visual rects for scroll corner/resizer and non-frame composited scroll bars.

third_party/WebKit/Source/core/paint/PaintLayerScrollableArea.cpp

Index: third_party/WebKit/Source/core/paint/PaintLayerScrollableArea.cpp
diff --git a/third_party/WebKit/Source/core/paint/PaintLayerScrollableArea.cpp b/third_party/WebKit/Source/core/paint/PaintLayerScrollableArea.cpp
index bf50af9a258f09dd7c7cc13fc9646c23df85c0c4..5d834b4a9271dec45bf361907cc061aa39cb981c 100644
--- a/third_party/WebKit/Source/core/paint/PaintLayerScrollableArea.cpp
+++ b/third_party/WebKit/Source/core/paint/PaintLayerScrollableArea.cpp
@@ -1095,7 +1095,7 @@ void PaintLayerScrollableArea::updateScrollCornerStyle()
     RefPtr<ComputedStyle> corner = box().hasOverflowClip() ? actualLayoutObject.getUncachedPseudoStyle(PseudoStyleRequest(PseudoIdScrollbarCorner), actualLayoutObject.style()) : PassRefPtr<ComputedStyle>(nullptr);
     if (corner) {
         if (!m_scrollCorner) {
-            m_scrollCorner = LayoutScrollbarPart::createAnonymous(&box().document());
+            m_scrollCorner = LayoutScrollbarPart::createAnonymous(&box().document(), this);
             m_scrollCorner->setDangerousOneWayParent(&box());
         }
         m_scrollCorner->setStyleWithWritingModeOfParent(corner.release());
@@ -1223,7 +1223,7 @@ void PaintLayerScrollableArea::updateResizerStyle()
     RefPtr<ComputedStyle> resizer = box().hasOverflowClip() ? actualLayoutObject.getUncachedPseudoStyle(PseudoStyleRequest(PseudoIdResizer), actualLayoutObject.style()) : PassRefPtr<ComputedStyle>(nullptr);
     if (resizer) {
         if (!m_resizer) {
-            m_resizer = LayoutScrollbarPart::createAnonymous(&box().document());
+            m_resizer = LayoutScrollbarPart::createAnonymous(&box().document(), this);
             m_resizer->setDangerousOneWayParent(&box());
         }
         m_resizer->setStyleWithWritingModeOfParent(resizer.release());